Quantum dots (QDs) are nanocrystalline particles with a radius less than or near the exciton Bohr radius and typically have a size particle size between 1 nm and 20 nm. Quantum dots have a quantum confinement effect and emit fluorescence when excited. Moreover, quantum dots have unique luminescence properties such as wide excitation peak width, narrow emission peak and tunable luminescence spectrum, which provide promising applications in the fields of photoluminescence and electroluminescence. A quantum dot light emitting diode (QLED) is a device that uses colloidal quantum dots as a light emitting layer and introduces the light emitting layer between different conductive materials to obtain light of a desired wavelength. QLED has advantages such as high color gamut, self-illumination, low starting voltage, quick response and so on; therefore currently it is a very hot research direction.